1. Field of the Invention
The present invention relates to an elastic wave device.
2. Description of the Related Art
Elastic wave devices are widely used, for example, in cellular phones. For example, Japanese Unexamined Patent Application Publication No. 2015-002511 discloses an elastic wave device having interdigital transducer (IDT) electrodes. Plural pads are disposed alongside portions of one main surface of a piezoelectric substrate of the elastic wave device.
In the piezoelectric substrate of the elastic wave device disclosed in Japanese Unexamined Patent Application Publication No. 2015-002511, polarization reversal easily occurs by the generation of electric charge due to the piezoelectric effect or the pyroelectric effect. Due to the occurrence of polarization reversal, the piezoelectricity may be decreased, which may also increase the insertion loss of the elastic wave device.